Hey Ronny. Supposedly the Elmarit 90's (M and R versions) are sharper across the frame wide open than their f2 counterparts, through the focus range. They are both incredible lenses, though. I opted for the R90 Cron and loved it, until I upgraded to the R80. But I don't have experience with the M versions, though.
Gregg
I haven't used the 90mm Elmarit lenses. But the latest R (V2 and I presume the latest M as well) are better performers than the Summicron 90mm counterparts. The 90 R Elmarit V2 is supposed to approach but not quite equal the 90mm Apo-Summicron-R Aspherical lens. But the Elmarit is a smaller, lighter and more manageable package.
And a few critters. These are nearly completely RAW OOC, LR sunlight profile, with some sharpening. The first one is cropped, and if your'e wondering, I didn't touch any colors / brightness for Painterly 1 and 2 - that's just how they ended up!:
The A7R did not go to the ballet recital this afternoon even though I really wanted the 135/2 APO Zeiss on it - but the darned loud shutter would have been awful. So the GX7 went instead. The A7r would be almost perfect for me if it had an electronic shutter . . . here's hoping they put one in on the A8R.
Anyways, I'll have the A7R out tomorrow on a hike and should have some images to show later on in the day!
A7r + Nikon 200mm f/2 ais. An absolute beast of a lens but there is nothing like it ! Think I'm going to really like this lens. Grabbed this LNIB copy from adorama. Once sony introduces the A8 with in body stabilization I expect the prices to skyrocket...